diff options
Diffstat (limited to 'drivers/mmc/mxsmmc.c')
| -rw-r--r-- | drivers/mmc/mxsmmc.c | 351 |
1 files changed, 351 insertions, 0 deletions
diff --git a/drivers/mmc/mxsmmc.c b/drivers/mmc/mxsmmc.c new file mode 100644 index 0000000000..2a9949eb94 --- /dev/null +++ b/drivers/mmc/mxsmmc.c @@ -0,0 +1,351 @@ +/* + * Freescale i.MX28 SSP MMC driver + * + * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com> + * on behalf of DENX Software Engineering GmbH + * + * Based on code from LTIB: + * (C) Copyright 2008-2010 Freescale Semiconductor, Inc. + * Terry Lv + * + * Copyright 2007, Freescale Semiconductor, Inc + * Andy Fleming + * + * Based vaguely on the pxa mmc code: + * (C) Copyright 2003 + * Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ +#include <common.h> +#include <malloc.h> +#include <mmc.h> +#include <asm/errno.h> +#include <asm/io.h> +#include <asm/arch/clock.h> +#include <asm/arch/imx-regs.h> +#include <asm/arch/sys_proto.h> + +struct mxsmmc_priv { + int id; + struct mx28_ssp_regs *regs; + uint32_t clkseq_bypass; + uint32_t *clkctrl_ssp; + uint32_t buswidth; + int (*mmc_is_wp)(int); +}; + +#define MXSMMC_MAX_TIMEOUT 10000 + +/* + * Sends a command out on the bus. Takes the mmc pointer, + * a command pointer, and an optional data pointer. + */ +static int +mxsmmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data) +{ + struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv; + struct mx28_ssp_regs *ssp_regs = priv->regs; + uint32_t reg; + int timeout; + uint32_t data_count; + uint32_t *data_ptr; + uint32_t ctrl0; + + debug("MMC%d: CMD%d\n", mmc->block_dev.dev, cmd->cmdidx); + + /* Check bus busy */ + timeout = MXSMMC_MAX_TIMEOUT; + while (--timeout) { + udelay(1000); + reg = readl(&ssp_regs->hw_ssp_status); + if (!(reg & + (SSP_STATUS_BUSY | SSP_STATUS_DATA_BUSY | + SSP_STATUS_CMD_BUSY))) { + break; + } + } + + if (!timeout) { + printf("MMC%d: Bus busy timeout!\n", mmc->block_dev.dev); + return TIMEOUT; + } + + /* See if card is present */ + if (readl(&ssp_regs->hw_ssp_status) & SSP_STATUS_CARD_DETECT) { + printf("MMC%d: No card detected!\n", mmc->block_dev.dev); + return NO_CARD_ERR; + } + + /* Start building CTRL0 contents */ + ctrl0 = priv->buswidth; + + /* Set up command */ + if (!(cmd->resp_type & MMC_RSP_CRC)) + ctrl0 |= SSP_CTRL0_IGNORE_CRC; + if (cmd->resp_type & MMC_RSP_PRESENT) /* Need to get response */ + ctrl0 |= SSP_CTRL0_GET_RESP; + if (cmd->resp_type & MMC_RSP_136) /* It's a 136 bits response */ + ctrl0 |= SSP_CTRL0_LONG_RESP; + + /* Command index */ + reg = readl(&ssp_regs->hw_ssp_cmd0); + reg &= ~(SSP_CMD0_CMD_MASK | SSP_CMD0_APPEND_8CYC); + reg |= cmd->cmdidx << SSP_CMD0_CMD_OFFSET; + if (cmd->cmdidx == MMC_CMD_STOP_TRANSMISSION) + reg |= SSP_CMD0_APPEND_8CYC; + writel(reg, &ssp_regs->hw_ssp_cmd0); + + /* Command argument */ + writel(cmd->cmdarg, &ssp_regs->hw_ssp_cmd1); + + /* Set up data */ + if (data) { + /* READ or WRITE */ + if (data->flags & MMC_DATA_READ) { + ctrl0 |= SSP_CTRL0_READ; + } else if (priv->mmc_is_wp(mmc->block_dev.dev)) { + printf("MMC%d: Can not write a locked card!\n", + mmc->block_dev.dev); + return UNUSABLE_ERR; + } + + ctrl0 |= SSP_CTRL0_DATA_XFER; + reg = ((data->blocks - 1) << + SSP_BLOCK_SIZE_BLOCK_COUNT_OFFSET) | + ((ffs(data->blocksize) - 1) << + SSP_BLOCK_SIZE_BLOCK_SIZE_OFFSET); + writel(reg, &ssp_regs->hw_ssp_block_size); + + reg = data->blocksize * data->blocks; + writel(reg, &ssp_regs->hw_ssp_xfer_size); + } + + /* Kick off the command */ + ctrl0 |= SSP_CTRL0_WAIT_FOR_IRQ | SSP_CTRL0_ENABLE | SSP_CTRL0_RUN; + writel(ctrl0, &ssp_regs->hw_ssp_ctrl0); + + /* Wait for the command to complete */ + timeout = MXSMMC_MAX_TIMEOUT; + while (--timeout) { + udelay(1000); + reg = readl(&ssp_regs->hw_ssp_status); + if (!(reg & SSP_STATUS_CMD_BUSY)) + break; + } + + if (!timeout) { + printf("MMC%d: Command %d busy\n", + mmc->block_dev.dev, cmd->cmdidx); + return TIMEOUT; + } + + /* Check command timeout */ + if (reg & SSP_STATUS_RESP_TIMEOUT) { + printf("MMC%d: Command %d timeout (status 0x%08x)\n", + mmc->block_dev.dev, cmd->cmdidx, reg); + return TIMEOUT; + } + + /* Check command errors */ + if (reg & (SSP_STATUS_RESP_CRC_ERR | SSP_STATUS_RESP_ERR)) { + printf("MMC%d: Command %d error (status 0x%08x)!\n", + mmc->block_dev.dev, cmd->cmdidx, reg); + return COMM_ERR; + } + + /* Copy response to response buffer */ + if (cmd->resp_type & MMC_RSP_136) { + cmd->response[3] = readl(&ssp_regs->hw_ssp_sdresp0); + cmd->response[2] = readl(&ssp_regs->hw_ssp_sdresp1); + cmd->response[1] = readl(&ssp_regs->hw_ssp_sdresp2); + cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp3); + } else + cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp0); + + /* Return if no data to process */ + if (!data) + return 0; + + /* Process the data */ + data_count = data->blocksize * data->blocks; + timeout = MXSMMC_MAX_TIMEOUT; + if (data->flags & MMC_DATA_READ) { + data_ptr = (uint32_t *)data->dest; + while (data_count && --timeout) { + reg = readl(&ssp_regs->hw_ssp_status); + if (!(reg & SSP_STATUS_FIFO_EMPTY)) { + *data_ptr++ = readl(&ssp_regs->hw_ssp_data); + data_count -= 4; + timeout = MXSMMC_MAX_TIMEOUT; + } else + udelay(1000); + } + } else { + data_ptr = (uint32_t *)data->src; + timeout *= 100; + while (data_count && --timeout) { + reg = readl(&ssp_regs->hw_ssp_status); + if (!(reg & SSP_STATUS_FIFO_FULL)) { + writel(*data_ptr++, &ssp_regs->hw_ssp_data); + data_count -= 4; + timeout = MXSMMC_MAX_TIMEOUT; + } else + udelay(1000); + } + } + + if (!timeout) { + printf("MMC%d: Data timeout with command %d (status 0x%08x)!\n", + mmc->block_dev.dev, cmd->cmdidx, reg); + return COMM_ERR; + } + + /* Check data errors */ + reg = readl(&ssp_regs->hw_ssp_status); + if (reg & + (SSP_STATUS_TIMEOUT | SSP_STATUS_DATA_CRC_ERR | + SSP_STATUS_FIFO_OVRFLW | SSP_STATUS_FIFO_UNDRFLW)) { + printf("MMC%d: Data error with command %d (status 0x%08x)!\n", + mmc->block_dev.dev, cmd->cmdidx, reg); + return COMM_ERR; + } + + return 0; +} + +static void mxsmmc_set_ios(struct mmc *mmc) +{ + struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv; + struct mx28_ssp_regs *ssp_regs = priv->regs; + + /* Set the clock speed */ + if (mmc->clock) + mx28_set_ssp_busclock(priv->id, mmc->clock / 1000); + + switch (mmc->bus_width) { + case 1: + priv->buswidth = SSP_CTRL0_BUS_WIDTH_ONE_BIT; + break; + case 4: + priv->buswidth = SSP_CTRL0_BUS_WIDTH_FOUR_BIT; + break; + case 8: + priv->buswidth = SSP_CTRL0_BUS_WIDTH_EIGHT_BIT; + break; + } + + /* Set the bus width */ + clrsetbits_le32(&ssp_regs->hw_ssp_ctrl0, + SSP_CTRL0_BUS_WIDTH_MASK, priv->buswidth); + + debug("MMC%d: Set %d bits bus width\n", + mmc->block_dev.dev, mmc->bus_width); +} + +static int mxsmmc_init(struct mmc *mmc) +{ + struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv; + struct mx28_ssp_regs *ssp_regs = priv->regs; + + /* Reset SSP */ + mx28_reset_block(&ssp_regs->hw_ssp_ctrl0_reg); + + /* 8 bits word length in MMC mode */ + clrsetbits_le32(&ssp_regs->hw_ssp_ctrl1, + SSP_CTRL1_SSP_MODE_MASK | SSP_CTRL1_WORD_LENGTH_MASK, + SSP_CTRL1_SSP_MODE_SD_MMC | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS); + + /* Set initial bit clock 400 KHz */ + mx28_set_ssp_busclock(priv->id, 400); + + /* Send initial 74 clock cycles (185 us @ 400 KHz)*/ + writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_set); + udelay(200); + writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_clr); + + return 0; +} + +int mxsmmc_initialize(bd_t *bis, int id, int (*wp)(int)) +{ + struct mx28_clkctrl_regs *clkctrl_regs = + (struct mx28_clkctrl_regs *)MXS_CLKCTRL_BASE; + struct mmc *mmc = NULL; + struct mxsmmc_priv *priv = NULL; + + mmc = malloc(sizeof(struct mmc)); + if (!mmc) + return -ENOMEM; + + priv = malloc(sizeof(struct mxsmmc_priv)); + if (!priv) { + free(mmc); + return -ENOMEM; + } + + priv->mmc_is_wp = wp; + priv->id = id; + switch (id) { + case 0: + priv->regs = (struct mx28_ssp_regs *)MXS_SSP0_BASE; + priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP0; + priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp0; + break; + case 1: + priv->regs = (struct mx28_ssp_regs *)MXS_SSP1_BASE; + priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP1; + priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp1; + break; + case 2: + priv->regs = (struct mx28_ssp_regs *)MXS_SSP2_BASE; + priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP2; + priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp2; + break; + case 3: + priv->regs = (struct mx28_ssp_regs *)MXS_SSP3_BASE; + priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP3; + priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp3; + break; + } + + sprintf(mmc->name, "MXS MMC"); + mmc->send_cmd = mxsmmc_send_cmd; + mmc->set_ios = mxsmmc_set_ios; + mmc->init = mxsmmc_init; + mmc->priv = priv; + + mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34; + + mmc->host_caps = MMC_MODE_4BIT | MMC_MODE_8BIT | + MMC_MODE_HS_52MHz | MMC_MODE_HS; + + /* + * SSPCLK = 480 * 18 / 29 / 1 = 297.731 MHz + * SSP bit rate = SSPCLK / (CLOCK_DIVIDE * (1 + CLOCK_RATE)), + * CLOCK_DIVIDE has to be an even value from 2 to 254, and + * CLOCK_RATE could be any integer from 0 to 255. + */ + mmc->f_min = 400000; + mmc->f_max = mxc_get_clock(MXC_SSP0_CLK + id) * 1000 / 2; + mmc->b_max = 0; + + mmc_register(mmc); + return 0; +} |